1. Technical Field
Embodiments relate to an organic light emitting display and power supply method thereof.
2. Description of the Related Art
Organic light emitting displays electrically excite a fluorescent or phosphorescent organic compound to emit light and operate N×M organic light emitting elements to display an image. Organic light emitting elements include an anode (ITO), an organic thin film, and a cathode (metal). The organic thin film has a multi-layer structure of an organic emission layer (EML) that emits light by a combination of electron and holes, an electron transporting layer (ETL) that transports electrons, a hole transporting layer (HTL) that transports holes, an electron injecting layer (EIL) that transports electron, and a hole injecting layer (HIL) that injects holes.
Organic light emitting displays provide good luminous efficiency, brightness, and visible angle, fast response speed, and are lightweight. Organic light emitting displays are used as a display of mobile information terminals, e.g., personal computers, cellular phones, PDAs, or the like, or as a display of various information devices.
Organic light emitting display include a driving circuit, a panel displaying an image, a controller controlling the panel, and a direct current power generator applying a direct current to the panel.
The direct current power generator uses a low voltage, e.g., a battery, as an initial input power. This initial input power then needs to be converted into a desired voltage in order to generate a voltage for emitting an organic light emitting element that is higher than the input power. In order to emit the organic light emitting element, the direct current power generator needs to simultaneously generate a high voltage EVLDD and a low voltage ELVSS, so that the direct current power generator comprises a plurality of devices, which increases a power consumption. The direct current power generator has a great amount of quiescent current, which is higher than a voltage applied to the organic light emitting panel when the organic light emitting panel operates at a low power display mode.